First report of extended-spectrum β-lactamases among clinical isolates of Escherichia coli in Gaza Strip, Palestine. (September 2016)

• Record Type: Journal Article
• Authors: Tayh, Ghassan; Ben Sallem, Rym; Ben Yahia, Houssem; Gharsa, Haythem; Klibi, Naouel; Boudabous, Abdellatif; Ben Slama, Karim
• Is Part Of: Journal of global antimicrobial resistance. Volume 6(2016:Sep.)
• Page Start: 17
• Page End: 21
• Publication Date: 2016-09
• Subjects: Escherichia coli -- ESBL -- blaCTX-M-15 -- Integron -- Gaza Strip -- Palestine; Drug resistance -- Periodicals; Drug resistance -- Periodicals; Drug resistance; Periodicals; 616.9041
• DOI: 10.1016/j.jgar.2016.01.013
• Languages: English
• ISSNs: 2213-7165

Abstract

Highlights: First detection of bla CTX-M and bla TEM β-lactamase genes in clinical Escherichia coli isolates from Gaza Strip hospitals. CTX-M-15 was the most prevalent β-lactamase detected among the ESBL-positive E. coli strains studied. ESBL phenotype disseminated in these hospitals is due to multiple enzymes found in ESBL-positive E. coli clinical isolates. E. coli isolates presented a high genetic diversity, indicating the potential horizontal transfer of ESBL genes. Abstract: This study aimed to assess the occurrence of extended-spectrum β-lactamases (ESBLs) in clinical Escherichia coli isolates from Palestine and to characterise their type, genetic environments and associated resistance genes. Twenty-seven broad-spectrum-cephalosporin-resistant E. coli isolates were recovered between April and June 2013 in Gaza Strip hospitals. Characterisation of ESBL genes and their genetic environments, detection of associated resistance genes, and the presence and characterisation of integrons were performed by PCR and sequencing. The clonal relationship among ESBL-positive E. coli strains was determined by pulsed-field gel electrophoresis (PFGE) using the restriction enzyme Xba I. Phylogroup typing and virulence factors were studied by PCR. The following ESBL genes were identified: bla CTX-M-15 (21 isolates); bla CTX-M-14a (2 isolates); bla CTX-M-1 (2 isolates); bla CTX-M-3 (1 isolate); and bla CTX-M-27 (1 isolate). The bla TEM-1 gene was also detected in eight CTX-M-producing strains. The IS Ecp1 sequence was found upstream of bla CTX-M in 23 isolates, and orf477 was found downstream of this gene in 24 isolates. IS 903 was also detected downstream in three isolates. Six isolates carried class 1 integrons with the gene cassette arrangement dfrA17 – aadA5 . High clonal diversity was observed among the studied isolates by PFGE (24 unrelated profiles). The virulence gene fimA was detected in 23 isolates, the aer gene in 8 isolates and the papC gene in 7 isolates. The studied isolates belonged to phylogroups B2 (12 isolates), D (12 isolates) and A (3 isolates). This is the first report of the detection of CTX-M class β-lactamases in E. coli of clinical origin in Gaza Strip hospitals.